Department of Nutrition, Center for Proteomics and Bioinformatics, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA.
Department of Population and Quantitative Health Sciences, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA.
Retrovirology. 2018 Jul 3;15(1):44. doi: 10.1186/s12977-018-0423-4.
Viral reprogramming of host cells enhances replication and is initiated by viral interaction with the cell surface. Upon human immunodeficiency virus (HIV) binding to CD4+ T cells, a signal transduction cascade is initiated that reorganizes the actin cytoskeleton, activates transcription factors, and alters mRNA splicing pathways.
We used a quantitative mass spectrometry-based phosphoproteomic approach to investigate signal transduction cascades initiated by CCR5-tropic HIV, which accounts for virtually all transmitted viruses and the vast majority of viruses worldwide.
CCR5-HIV signaling induced significant reprogramming of the actin cytoskeleton and mRNA splicing pathways, as previously described. In addition, CCR5-HIV signaling induced profound changes to the mRNA transcription, processing, translation, and post-translational modifications pathways, indicating that virtually every stage of protein production is affected. Furthermore, we identified two kinases regulated by CCR5-HIV signaling-p70-S6K1 (RPS6KB1) and MK2 (MAPKAPK2)-that were also required for optimal HIV infection of CD4+ T cells. These kinases regulate protein translation and cytoskeletal architecture, respectively, reinforcing the importance of these pathways in viral replication. Additionally, we found that blockade of CCR5 signaling by maraviroc had relatively modest effects on CCR5-HIV signaling, in agreement with reports that signaling by CCR5 is dispensable for HIV infection but in contrast to the critical effects of CXCR4 on cortical actin reorganization.
These results demonstrate that CCR5-tropic HIV induces significant reprogramming of host CD4+ T cell protein production pathways and identifies two novel kinases induced upon viral binding to the cell surface that are critical for HIV replication in host cells.
病毒对宿主细胞的重编程增强了复制，并由病毒与细胞表面的相互作用引发。当人类免疫缺陷病毒 (HIV) 与 CD4+T 细胞结合时，会启动信号转导级联反应，重新组织肌动蛋白细胞骨架，激活转录因子，并改变 mRNA 剪接途径。
我们使用基于定量质谱的磷酸化蛋白质组学方法来研究 CCR5 嗜性 HIV 引发的信号转导级联反应，该病毒几乎可以感染所有传播的病毒和全球绝大多数病毒。
如前所述，CCR5-HIV 信号诱导肌动蛋白细胞骨架和 mRNA 剪接途径的显著重编程。此外，CCR5-HIV 信号诱导 mRNA 转录、加工、翻译和翻译后修饰途径的深刻变化，表明实际上蛋白质生产的每个阶段都受到影响。此外，我们发现两种受 CCR5-HIV 信号调节的激酶-p70-S6K1（RPS6KB1）和 MK2（MAPKAPK2）-也需要最佳的 HIV 感染 CD4+T 细胞。这些激酶分别调节蛋白质翻译和细胞骨架结构，这加强了这些途径在病毒复制中的重要性。此外，我们发现马拉维若通过阻断 CCR5 信号对 CCR5-HIV 信号的影响相对较小，这与 CCR5 信号对 HIV 感染不是必需的报告一致，但与 CXCR4 对皮质肌动蛋白重排的关键作用形成对比。
这些结果表明，CCR5 嗜性 HIV 诱导宿主 CD4+T 细胞蛋白质产生途径的显著重编程，并确定了两种新型激酶，这些激酶在病毒与细胞表面结合后被诱导，对于宿主细胞中的 HIV 复制至关重要。
